The solution you are looking for resides with the Server-Push technologies.
The .Net framework provides a solution for two way communication via the WCF Callbacks. More information here.
The signalR framework provides pushing data to the Client Side, so it is better for MVC like applications and not so much on DevExpress Tools that do most of the databinding on the ServerSide. Info on signalR can be found here.
DevExpress sugests a solution with timers (PostBacks after a certain time has passed).
On a general note html 5 provides the WebSocket functionality, which is essentially what all the other options use on a part. Frameworks like the above, build on the technologies but also provide walk-arounds by using timers and such.